don't try to chase unaligned pointer.

XXX memcpy() can be optimized in wacky way.  not sure if the use of
safememcpy() is enough...

diff --git a/ipsec_doi.h b/ipsec_doi.h
index af7a57823b7ff5023454fda8ec75e5114658917d..3d7608fdb9959d7f563c19223a9b530f50a1760d 100644 (file)
--- a/ipsec_doi.h
+++ b/ipsec_doi.h
@@ -26,7 +26,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-/* YIPS @(#)$Id: ipsec_doi.h,v 1.2 2000-09-29 20:42:34 itojun Exp $ */
+/* YIPS @(#)$Id: ipsec_doi.h,v 1.3 2000-10-03 05:16:38 itojun Exp $ */
 
 /* refer to RFC 2407 */
 
@@ -109,12 +109,12 @@ struct ipsecdoi_sa {
        struct isakmp_gen h;
        u_int32_t doi; /* Domain of Interpretation */
        u_int32_t sit; /* Situation */
-} __attribute__((__packed__));
+};
 
 struct ipsecdoi_secrecy_h {
        u_int16_t len;
        u_int16_t reserved;
-} __attribute__((__packed__));
+};
 
 /* 4.6.2.1 Identification Type Values */
 struct ipsecdoi_id {
@@ -123,7 +123,7 @@ struct ipsecdoi_id {
        u_int8_t  proto_id;     /* Protocol ID */
        u_int16_t port;         /* Port */
        /* Identification Data */
-} __attribute__((__packed__));
+};
 
 #define IPSECDOI_ID_IPV4_ADDR                        1
 #define IPSECDOI_ID_FQDN                             2

diff --git a/isakmp.h b/isakmp.h
index d9029970c47c4275a23e6ec840bf0b9ee9304a26..70bc5efe9198018500fcce1be913b6b093ccf54a 100644 (file)
--- a/isakmp.h
+++ b/isakmp.h
@@ -26,7 +26,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-/* YIPS @(#)$Id: isakmp.h,v 1.6 2000-09-29 20:42:35 itojun Exp $ */
+/* YIPS @(#)$Id: isakmp.h,v 1.7 2000-10-03 05:16:38 itojun Exp $ */
 
 /* refer to RFC 2408 */
 
@@ -41,7 +41,7 @@ typedef u_char msgid_t[4];
 typedef struct { /* i_cookie + r_cookie */
        cookie_t i_ck;
        cookie_t r_ck;
-} __attribute__((__packed__)) isakmp_index;
+} isakmp_index;
 
 #define INITIATOR       1
 #define RESPONDER       2
@@ -110,7 +110,7 @@ struct isakmp {
        u_int8_t flags;         /* Flags */
        msgid_t msgid;
        u_int32_t len;          /* Length */
-} __attribute__((__packed__));
+};
 
 /* Next Payload Type */
 #define ISAKMP_NPTYPE_NONE   0 /* NONE*/
@@ -153,7 +153,7 @@ struct isakmp_gen {
        u_int8_t  np;       /* Next Payload */
        u_int8_t  reserved; /* RESERVED, unused, must set to 0 */
        u_int16_t len;      /* Payload Length */
-} __attribute__((__packed__));
+};
 
 /* 3.3 Data Attributes
          0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
@@ -170,7 +170,7 @@ struct isakmp_data {
        u_int16_t lorv;     /* if f equal 1, Attribute Length */
                          /* if f equal 0, Attribute Value */
        /* if f equal 1, Attribute Value */
-} __attribute__((__packed__));
+};
 #define ISAKMP_GEN_TLV 0x0000
 #define ISAKMP_GEN_TV  0x8000
        /* mask for type of attribute format */
@@ -192,7 +192,7 @@ struct isakmp_pl_sa {
        struct isakmp_gen h;
        u_int32_t doi; /* Domain of Interpretation */
        u_int32_t sit; /* Situation */
-} __attribute__((__packed__));
+};
 
 /* 3.5 Proposal Payload */
        /*
@@ -209,7 +209,7 @@ struct isakmp_pl_p {
        u_int8_t spi_size;  /* SPI Size */
        u_int8_t num_t;     /* Number of Transforms */
        /* SPI */
-} __attribute__((__packed__));
+};
 
 /* 3.6 Transform Payload */
        /*
@@ -224,13 +224,13 @@ struct isakmp_pl_t {
        u_int8_t  t_id;     /* Transform-Id */
        u_int16_t reserved; /* RESERVED2 */
        /* SA Attributes */
-} __attribute__((__packed__));
+};
 
 /* 3.7 Key Exchange Payload */
 struct isakmp_pl_ke {
        struct isakmp_gen h;
        /* Key Exchange Data */
-} __attribute__((__packed__));
+};
 
 /* 3.8 Identification Payload */
        /* MUST NOT to be used, because of being defined in ipsec-doi. */
@@ -241,7 +241,7 @@ struct isakmp_pl_id {
                u_int32_t doi_data;  /* DOI Specific ID Data */
        } d;
        /* Identification Data */
-} __attribute__((__packed__));
+};
 
 /* 3.9 Certificate Payload */
 struct isakmp_pl_cert {
@@ -253,7 +253,7 @@ struct isakmp_pl_cert {
                certificate or certificate-related information contained in the
                Certificate Data field.
                */
-} __attribute__((__packed__));
+};
 
 /* Certificate Type */
 #define ISAKMP_CERT_NONE   0
@@ -279,28 +279,28 @@ struct isakmp_pl_cr {
        */
        /* # Certificate Authorities (1 octet) */
        /* Certificate Authorities (variable length) */
-} __attribute__((__packed__));
+};
 
 /* 3.11 Hash Payload */
        /* may not be used, because of having only data. */
 struct isakmp_pl_hash {
        struct isakmp_gen h;
        /* Hash Data */
-} __attribute__((__packed__));
+};
 
 /* 3.12 Signature Payload */
        /* may not be used, because of having only data. */
 struct isakmp_pl_sig {
        struct isakmp_gen h;
        /* Signature Data */
-} __attribute__((__packed__));
+};
 
 /* 3.13 Nonce Payload */
        /* may not be used, because of having only data. */
 struct isakmp_pl_nonce {
        struct isakmp_gen h;
        /* Nonce Data */
-} __attribute__((__packed__));
+};
 
 /* 3.14 Notification Payload */
 struct isakmp_pl_n {
@@ -311,7 +311,7 @@ struct isakmp_pl_n {
        u_int16_t type;     /* Notify Message Type */
        /* SPI */
        /* Notification Data */
-} __attribute__((__packed__));
+};
 
 /* 3.14.1 Notify Message Types */
 /* NOTIFY MESSAGES - ERROR TYPES */
@@ -354,20 +354,20 @@ struct isakmp_pl_d {
        u_int8_t  spi_size; /* SPI Size */
        u_int16_t num_spi;  /* # of SPIs */
        /* SPI(es) */
-} __attribute__((__packed__));
+};
 
 \f
 struct isakmp_ph1tab {
        struct isakmp_ph1 *head;
        struct isakmp_ph1 *tail;
        int len;
-} __attribute__((__packed__));
+};
 
 struct isakmp_ph2tab {
        struct isakmp_ph2 *head;
        struct isakmp_ph2 *tail;
        int len;
-} __attribute__((__packed__));
+};
 
 #define EXCHANGE_PROXY   1
 #define EXCHANGE_MYSELF  0

diff --git a/print-isakmp.c b/print-isakmp.c
index a3963f2ad345e8dad2abdea425e9f99a3f307a0a..513bfcc6c1f3af5ca0e9d6cafe7a46d64967662c 100644 (file)
--- a/print-isakmp.c
+++ b/print-isakmp.c
@@ -30,7 +30,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-isakmp.c,v 1.22 2000-10-03 02:54:59 itojun Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-isakmp.c,v 1.23 2000-10-03 05:16:38 itojun Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -99,6 +99,7 @@ static u_char *isakmp_sub0_print(u_char, struct isakmp_gen *, u_char *,
 static u_char *isakmp_sub_print(u_char, struct isakmp_gen *, u_char *,
        u_int32_t, u_int32_t, u_int32_t);
 static char *numstr(int);
+static void safememcpy(void *, void *, size_t);
 
 #define MAXINITIATORS  20
 int ninitiator = 0;
@@ -420,7 +421,7 @@ static u_char *
 isakmp_sa_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_sa *p;
+       struct isakmp_pl_sa *p, sa;
        u_int32_t *q;
        u_int32_t doi;
        u_int32_t sit;
@@ -430,15 +431,16 @@ isakmp_sa_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_SA));
 
        p = (struct isakmp_pl_sa *)ext;
-       doi = ntohl(p->doi);
+       safememcpy(&sa, ext, sizeof(sa));
+       doi = ntohl(sa.doi);
        if (doi != 1) {
                printf(" doi=%d", doi);
-               printf(" situation=%u", (u_int32_t)ntohl(p->sit));
+               printf(" situation=%u", (u_int32_t)ntohl(sa.sit));
                return (u_char *)(p + 1);
        }
 
        printf(" doi=ipsec");
-       q = (u_int32_t *)&p->sit;
+       q = (u_int32_t *)&sa.sit;
        printf(" situation=");
        t = 0;
        if (ntohl(*q) & 0x01) {
@@ -467,23 +469,24 @@ static u_char *
 isakmp_p_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_p *p;
+       struct isakmp_pl_p *p, prop;
        u_char *cp;
 
        printf("%s:", NPSTR(ISAKMP_NPTYPE_P));
 
        p = (struct isakmp_pl_p *)ext;
+       safememcpy(&prop, ext, sizeof(prop));
        printf(" #%d protoid=%s transform=%d",
-               p->p_no, PROTOIDSTR(p->prot_id), p->num_t);
-       if (p->spi_size) {
+               prop.p_no, PROTOIDSTR(prop.prot_id), prop.num_t);
+       if (prop.spi_size) {
                printf(" spi=");
-               rawprint((caddr_t)(p + 1), p->spi_size);
+               rawprint((caddr_t)(p + 1), prop.spi_size);
        }
 
-       ext = (struct isakmp_gen *)((u_char *)(p + 1) + p->spi_size);
+       ext = (struct isakmp_gen *)((u_char *)(p + 1) + prop.spi_size);
 
        cp = isakmp_sub_print(ISAKMP_NPTYPE_T, ext, ep, phase, doi0,
-               p->prot_id);
+               prop.prot_id);
 
        return cp;
 }
@@ -546,7 +549,7 @@ static u_char *
 isakmp_t_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
-       struct isakmp_pl_t *p;
+       struct isakmp_pl_t *p, t;
        u_char *cp;
        char *idstr;
        struct attrmap *map;
@@ -556,25 +559,26 @@ isakmp_t_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_T));
 
        p = (struct isakmp_pl_t *)ext;
+       safememcpy(&t, ext, sizeof(t));
 
        switch (proto) {
        case 1:
-               idstr = STR_OR_ID(p->t_id, isakmp_p_map);
+               idstr = STR_OR_ID(t.t_id, isakmp_p_map);
                map = oakley_t_map;
                nmap = sizeof(oakley_t_map)/sizeof(oakley_t_map[0]);
                break;
        case 2:
-               idstr = STR_OR_ID(p->t_id, ah_p_map);
+               idstr = STR_OR_ID(t.t_id, ah_p_map);
                map = ipsec_t_map;
                nmap = sizeof(ipsec_t_map)/sizeof(ipsec_t_map[0]);
                break;
        case 3:
-               idstr = STR_OR_ID(p->t_id, esp_p_map);
+               idstr = STR_OR_ID(t.t_id, esp_p_map);
                map = ipsec_t_map;
                nmap = sizeof(ipsec_t_map)/sizeof(ipsec_t_map[0]);
                break;
        case 4:
-               idstr = STR_OR_ID(p->t_id, ipcomp_p_map);
+               idstr = STR_OR_ID(t.t_id, ipcomp_p_map);
                map = ipsec_t_map;
                nmap = sizeof(ipsec_t_map)/sizeof(ipsec_t_map[0]);
                break;
@@ -586,11 +590,11 @@ isakmp_t_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        }
 
        if (idstr)
-               printf(" #%d id=%s ", p->t_no, idstr);
+               printf(" #%d id=%s ", t.t_no, idstr);
        else
-               printf(" #%d id=%d ", p->t_no, p->t_id);
+               printf(" #%d id=%d ", t.t_no, t.t_id);
        cp = (u_char *)(p + 1);
-       ep2 = (u_char *)p + ntohs(ext->len);
+       ep2 = (u_char *)p + ntohs(t.h.len);
        while (cp < ep && cp < ep2) {
                if (map && nmap) {
                        cp = isakmp_attrmap_print(cp, (ep < ep2) ? ep : ep2,
@@ -607,14 +611,17 @@ static u_char *
 isakmp_ke_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
+       struct isakmp_gen e;
+
        printf("%s:", NPSTR(ISAKMP_NPTYPE_KE));
 
-       printf(" key len=%d", ntohs(ext->len) - 4);
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&e, ext, sizeof(e));
+       printf(" key len=%d", ntohs(e.len) - 4);
+       if (2 < vflag && 4 < ntohs(e.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(e.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(e.len);
 }
 
 static u_char *
@@ -622,7 +629,7 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
 #define USE_IPSECDOI_IN_PHASE1 1
-       struct isakmp_pl_id *p;
+       struct isakmp_pl_id *p, id;
        static char *idtypestr[] = {
                "IPv4", "IPv4net", "IPv6", "IPv6net",
        };
@@ -637,11 +644,12 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_ID));
 
        p = (struct isakmp_pl_id *)ext;
-       if (sizeof(*p) < ext->len)
+       safememcpy(&id, ext, sizeof(id));
+       if (sizeof(*p) < id.h.len)
                data = (u_char *)(p + 1);
        else
                data = NULL;
-       len = ntohs(ext->len) - sizeof(*p);
+       len = ntohs(id.h.len) - sizeof(*p);
 
 #if 0 /*debug*/
        printf(" [phase=%d doi=%d proto=%d]", phase, doi, proto);
@@ -651,9 +659,9 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        case 1:
 #endif
        default:
-               printf(" idtype=%s", STR_OR_ID(p->d.id_type, idtypestr));
+               printf(" idtype=%s", STR_OR_ID(id.d.id_type, idtypestr));
                printf(" doi_data=%u",
-                       (u_int32_t)(ntohl(p->d.doi_data) & 0xffffff));
+                       (u_int32_t)(ntohl(id.d.doi_data) & 0xffffff));
                break;
 
 #ifdef USE_IPSECDOI_IN_PHASE1
@@ -661,14 +669,15 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
 #endif
        case 2:
            {
-               struct ipsecdoi_id *p;
+               struct ipsecdoi_id *p, id;
                struct protoent *pe;
 
                p = (struct ipsecdoi_id *)ext;
-               printf(" idtype=%s", STR_OR_ID(p->type, ipsecidtypestr));
-               if (p->proto_id) {
+               safememcpy(&id, ext, sizeof(id));
+               printf(" idtype=%s", STR_OR_ID(id.type, ipsecidtypestr));
+               if (id.proto_id) {
                        setprotoent(1);
-                       pe = getprotobynumber(p->proto_id);
+                       pe = getprotobynumber(id.proto_id);
                        if (pe)
                                printf(" protoid=%s", pe->p_name);
                        endprotoent();
@@ -676,10 +685,10 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
                        /* it DOES NOT mean IPPROTO_IP! */
                        printf(" protoid=%s", "0");
                }
-               printf(" port=%d", ntohs(p->port));
+               printf(" port=%d", ntohs(id.port));
                if (!len)
                        break;
-               switch (p->type) {
+               switch (id.type) {
                case IPSECDOI_ID_IPV4_ADDR:
                        printf(" len=%d %s", len, ipaddr_string(data));
                        len = 0;
@@ -753,14 +762,14 @@ isakmp_id_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
                        rawprint((caddr_t)data, len);
                }
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(id.h.len);
 }
 
 static u_char *
 isakmp_cert_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_cert *p;
+       struct isakmp_pl_cert *p, cert;
        static char *certstr[] = {
                "none", "pkcs7", "pgp", "dns",
                "x509sign", "x509ke", "kerberos", "crl",
@@ -770,20 +779,21 @@ isakmp_cert_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_CERT));
 
        p = (struct isakmp_pl_cert *)ext;
-       printf(" len=%d", ntohs(ext->len) - 4);
-       printf(" type=%s", STR_OR_ID((p->encode), certstr));
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&cert, ext, sizeof(cert));
+       printf(" len=%d", ntohs(cert.h.len) - 4);
+       printf(" type=%s", STR_OR_ID((cert.encode), certstr));
+       if (2 < vflag && 4 < ntohs(cert.h.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(cert.h.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(cert.h.len);
 }
 
 static u_char *
 isakmp_cr_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_cert *p;
+       struct isakmp_pl_cert *p, cert;
        static char *certstr[] = {
                "none", "pkcs7", "pgp", "dns",
                "x509sign", "x509ke", "kerberos", "crl",
@@ -793,62 +803,72 @@ isakmp_cr_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_CR));
 
        p = (struct isakmp_pl_cert *)ext;
-       printf(" len=%d", ntohs(ext->len) - 4);
-       printf(" type=%s", STR_OR_ID((p->encode), certstr));
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&cert, ext, sizeof(cert));
+       printf(" len=%d", ntohs(cert.h.len) - 4);
+       printf(" type=%s", STR_OR_ID((cert.encode), certstr));
+       if (2 < vflag && 4 < ntohs(cert.h.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(cert.h.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(cert.h.len);
 }
 
 static u_char *
 isakmp_hash_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
+       struct isakmp_gen e;
+
        printf("%s:", NPSTR(ISAKMP_NPTYPE_HASH));
 
-       printf(" len=%d", ntohs(ext->len) - 4);
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&e, ext, sizeof(e));
+       printf(" len=%d", ntohs(e.len) - 4);
+       if (2 < vflag && 4 < ntohs(e.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(e.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(e.len);
 }
 
 static u_char *
 isakmp_sig_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
+       struct isakmp_gen e;
+
        printf("%s:", NPSTR(ISAKMP_NPTYPE_SIG));
 
-       printf(" len=%d", ntohs(ext->len) - 4);
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&e, ext, sizeof(e));
+       printf(" len=%d", ntohs(e.len) - 4);
+       if (2 < vflag && 4 < ntohs(e.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(e.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(e.len);
 }
 
 static u_char *
 isakmp_nonce_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
+       struct isakmp_gen e;
+
        printf("%s:", NPSTR(ISAKMP_NPTYPE_NONCE));
 
-       printf(" n len=%d", ntohs(ext->len) - 4);
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&e, ext, sizeof(e));
+       printf(" n len=%d", ntohs(e.len) - 4);
+       if (2 < vflag && 4 < ntohs(e.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(e.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(e.len);
 }
 
 static u_char *
 isakmp_n_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_n *p;
+       struct isakmp_pl_n *p, n;
        u_char *cp;
        u_char *ep2;
        u_int32_t doi;
@@ -884,42 +904,43 @@ isakmp_n_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_N));
 
        p = (struct isakmp_pl_n *)ext;
-       doi = ntohl(p->doi);
-       proto = p->prot_id;
+       safememcpy(&n, ext, sizeof(n));
+       doi = ntohl(n.doi);
+       proto = n.prot_id;
        if (doi != 1) {
                printf(" doi=%d", doi);
                printf(" proto=%d", proto);
-               printf(" type=%s", NOTIFYSTR(ntohs(p->type)));
-               if (p->spi_size) {
+               printf(" type=%s", NOTIFYSTR(ntohs(n.type)));
+               if (n.spi_size) {
                        printf(" spi=");
-                       rawprint((caddr_t)(p + 1), p->spi_size);
+                       rawprint((caddr_t)(p + 1), n.spi_size);
                }
-               return (u_char *)(p + 1) + p->spi_size;
+               return (u_char *)(p + 1) + n.spi_size;
        }
 
        printf(" doi=ipsec");
        printf(" proto=%s", PROTOIDSTR(proto));
-       if (ntohs(p->type) < 8192)
-               printf(" type=%s", NOTIFYSTR(ntohs(p->type)));
-       else if (ntohs(p->type) < 16384)
-               printf(" type=%s", IPSECNOTIFYSTR(ntohs(p->type)));
-       else if (ntohs(p->type) < 24576)
-               printf(" type=%s", NOTIFYSTR(ntohs(p->type)));
-       else if (ntohs(p->type) < 40960)
-               printf(" type=%s", IPSECNOTIFYSTR(ntohs(p->type)));
+       if (ntohs(n.type) < 8192)
+               printf(" type=%s", NOTIFYSTR(ntohs(n.type)));
+       else if (ntohs(n.type) < 16384)
+               printf(" type=%s", IPSECNOTIFYSTR(ntohs(n.type)));
+       else if (ntohs(n.type) < 24576)
+               printf(" type=%s", NOTIFYSTR(ntohs(n.type)));
+       else if (ntohs(n.type) < 40960)
+               printf(" type=%s", IPSECNOTIFYSTR(ntohs(n.type)));
        else
-               printf(" type=%s", NOTIFYSTR(ntohs(p->type)));
-       if (p->spi_size) {
+               printf(" type=%s", NOTIFYSTR(ntohs(n.type)));
+       if (n.spi_size) {
                printf(" spi=");
-               rawprint((caddr_t)(p + 1), p->spi_size);
+               rawprint((caddr_t)(p + 1), n.spi_size);
        }
 
-       cp = (u_char *)(p + 1) + p->spi_size;
-       ep2 = (u_char *)p + ntohs(ext->len);
+       cp = (u_char *)(p + 1) + n.spi_size;
+       ep2 = (u_char *)p + ntohs(n.h.len);
 
        if (cp < ep) {
                printf(" orig=(");
-               switch (ntohs(p->type)) {
+               switch (ntohs(n.type)) {
                case IPSECDOI_NTYPE_RESPONDER_LIFETIME:
                    {
                        struct attrmap *map = oakley_t_map;
@@ -941,19 +962,19 @@ isakmp_n_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
                default:
                        /* NULL is dummy */
                        isakmp_print(cp,
-                               ntohs(ext->len) - sizeof(*p) - p->spi_size,
+                               ntohs(n.h.len) - sizeof(*p) - n.spi_size,
                                NULL);
                }
                printf(")");
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(n.h.len);
 }
 
 static u_char *
 isakmp_d_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi0, u_int32_t proto0)
 {
-       struct isakmp_pl_d *p;
+       struct isakmp_pl_d *p, d;
        u_int8_t *q;
        u_int32_t doi;
        u_int32_t proto;
@@ -962,8 +983,9 @@ isakmp_d_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        printf("%s:", NPSTR(ISAKMP_NPTYPE_D));
 
        p = (struct isakmp_pl_d *)ext;
-       doi = ntohl(p->doi);
-       proto = p->prot_id;
+       safememcpy(&d, ext, sizeof(d));
+       doi = ntohl(d.doi);
+       proto = d.prot_id;
        if (doi != 1) {
                printf(" doi=%u", doi);
                printf(" proto=%u", proto);
@@ -971,15 +993,15 @@ isakmp_d_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
                printf(" doi=ipsec");
                printf(" proto=%s", PROTOIDSTR(proto));
        }
-       printf(" spilen=%u", p->spi_size);
-       printf(" nspi=%u", ntohs(p->num_spi));
+       printf(" spilen=%u", d.spi_size);
+       printf(" nspi=%u", ntohs(d.num_spi));
        printf(" spi=");
        q = (u_int8_t *)(p + 1);
-       for (i = 0; i < ntohs(p->num_spi); i++) {
+       for (i = 0; i < ntohs(d.num_spi); i++) {
                if (i != 0)
                        printf(",");
-               rawprint((caddr_t)q, p->spi_size);
-               q += p->spi_size;
+               rawprint((caddr_t)q, d.spi_size);
+               q += d.spi_size;
        }
        return q;
 }
@@ -988,14 +1010,17 @@ static u_char *
 isakmp_vid_print(struct isakmp_gen *ext, u_char *ep, u_int32_t phase,
        u_int32_t doi, u_int32_t proto)
 {
+       struct isakmp_gen e;
+
        printf("%s:", NPSTR(ISAKMP_NPTYPE_VID));
 
-       printf(" len=%d", ntohs(ext->len) - 4);
-       if (2 < vflag && 4 < ntohs(ext->len)) {
+       safememcpy(&e, ext, sizeof(e));
+       printf(" len=%d", ntohs(e.len) - 4);
+       if (2 < vflag && 4 < ntohs(e.len)) {
                printf(" ");
-               rawprint((caddr_t)(ext + 1), ntohs(ext->len) - 4);
+               rawprint((caddr_t)(ext + 1), ntohs(e.len) - 4);
        }
-       return (u_char *)ext + ntohs(ext->len);
+       return (u_char *)ext + ntohs(e.len);
 }
 
 static u_char *
@@ -1003,14 +1028,16 @@ isakmp_sub0_print(u_char np, struct isakmp_gen *ext, u_char *ep,
        u_int32_t phase, u_int32_t doi, u_int32_t proto)
 {
        u_char *cp;
+       struct isakmp_gen e;
 
        cp = (u_char *)ext;
+       safememcpy(&e, ext, sizeof(e));
 
        if (NPFUNC(np))
                cp = (*NPFUNC(np))(ext, ep, phase, doi, proto);
        else {
                printf("%s", NPSTR(np));
-               cp += ntohs(ext->len);
+               cp += ntohs(e.len);
        }
        return cp;
 }
@@ -1022,11 +1049,14 @@ isakmp_sub_print(u_char np, struct isakmp_gen *ext, u_char *ep,
        u_char *cp;
        static int depth = 0;
        int i;
+       struct isakmp_gen e;
 
        cp = (u_char *)ext;
 
        while (np) {
-               if (ep < (u_char *)ext + ntohs(ext->len)) {
+               safememcpy(&e, ext, sizeof(e));
+
+               if (ep < (u_char *)ext + ntohs(e.len)) {
                        printf(" [|%s]", NPSTR(np));
                        cp = ep + 1;
                        break;
@@ -1040,7 +1070,7 @@ isakmp_sub_print(u_char np, struct isakmp_gen *ext, u_char *ep,
                printf(")");
                depth--;
 
-               np = ext->np;
+               np = e.np;
                ext = (struct isakmp_gen *)cp;
        }
        return cp;
@@ -1054,59 +1084,72 @@ numstr(int x)
        return buf;
 }
 
+/*
+ * some compiler tries to optimize memcpy(), using the alignment constraint
+ * on the argument pointer type.  by using this function, we try to avoid the
+ * optimization.
+ */
+static void
+safememcpy(void *p, void *q, size_t l)
+{
+       memcpy(p, q, l);
+}
+
 void
 isakmp_print(const u_char *bp, u_int length, const u_char *bp2)
 {
-       struct isakmp *base;
+       struct isakmp *p, base;
        u_char *ep;
        u_char np;
        int i;
        int phase;
        int major, minor;
 
-       base = (struct isakmp *)bp;
+       p = (struct isakmp *)bp;
        ep = (u_char *)snapend;
 
-       if ((struct isakmp *)ep < base + 1) {
+       if ((struct isakmp *)ep < p + 1) {
                printf("[|isakmp]");
                return;
        }
 
+       safememcpy(&base, p, sizeof(base));
+
        printf("isakmp");
        if (vflag) {
-               major = (base->vers & ISAKMP_VERS_MAJOR)
+               major = (base.vers & ISAKMP_VERS_MAJOR)
                                >> ISAKMP_VERS_MAJOR_SHIFT;
-               minor = (base->vers & ISAKMP_VERS_MINOR)
+               minor = (base.vers & ISAKMP_VERS_MINOR)
                                >> ISAKMP_VERS_MINOR_SHIFT;
                printf(" %d.%d", major, minor);
        }
 
        if (vflag) {
                printf(" msgid ");
-               rawprint((caddr_t)&base->msgid, sizeof(base->msgid));
+               rawprint((caddr_t)&base.msgid, sizeof(base.msgid));
        }
 
        if (1 < vflag) {
                printf(" cookie ");
-               rawprint((caddr_t)&base->i_ck, sizeof(base->i_ck));
+               rawprint((caddr_t)&base.i_ck, sizeof(base.i_ck));
                printf("->");
-               rawprint((caddr_t)&base->r_ck, sizeof(base->r_ck));
+               rawprint((caddr_t)&base.r_ck, sizeof(base.r_ck));
        }
        printf(":");
 
-       phase = (*(u_int32_t *)base->msgid == 0) ? 1 : 2;
+       phase = (*(u_int32_t *)base.msgid == 0) ? 1 : 2;
        if (phase == 1)
                printf(" phase %d", phase);
        else
                printf(" phase %d/others", phase);
 
-       i = cookie_find(&base->i_ck);
+       i = cookie_find(&base.i_ck);
        if (i < 0) {
-               if (iszero((u_char *)&base->r_ck, sizeof(base->r_ck))) {
+               if (iszero((u_char *)&base.r_ck, sizeof(base.r_ck))) {
                        /* the first packet */
                        printf(" I");
                        if (bp2)
-                               cookie_record(&base->i_ck, bp2);
+                               cookie_record(&base.i_ck, bp2);
                } else
                        printf(" ?");
        } else {
@@ -1118,10 +1161,10 @@ isakmp_print(const u_char *bp, u_int length, const u_char *bp2)
                        printf(" ?");
        }
 
-       printf(" %s", ETYPESTR(base->etype));
-       if (base->flags) {
-               printf("[%s%s]", base->flags & ISAKMP_FLAG_E ? "E" : "",
-                       base->flags & ISAKMP_FLAG_C ? "C" : "");
+       printf(" %s", ETYPESTR(base.etype));
+       if (base.flags) {
+               printf("[%s%s]", base.flags & ISAKMP_FLAG_E ? "E" : "",
+                       base.flags & ISAKMP_FLAG_C ? "C" : "");
        }
        printf(":");
 
@@ -1136,28 +1179,28 @@ isakmp_print(const u_char *bp, u_int length, const u_char *bp2)
        }
 
        /* regardless of phase... */
-       if (base->flags & ISAKMP_FLAG_E) {
+       if (base.flags & ISAKMP_FLAG_E) {
                /*
                 * encrypted, nothing we can do right now.
                 * we hope to decrypt the packet in the future...
                 */
-               printf(" [|%s]", NPSTR(base->np));
+               printf(" [|%s]", NPSTR(base.np));
                goto done;
        }
 
        nparen = 0;
-       CHECKLEN(base + 1, base->np)
+       CHECKLEN(p + 1, base.np)
 
-       np = base->np;
-       ext = (struct isakmp_gen *)(base + 1);
+       np = base.np;
+       ext = (struct isakmp_gen *)(p + 1);
        isakmp_sub_print(np, ext, ep, phase, 0, 0);
     }
 
 done:
        if (vflag) {
-               if (ntohl(base->len) != length) {
+               if (ntohl(base.len) != length) {
                        printf(" (len mismatch: isakmp %u/ip %d)",
-                               (u_int32_t)ntohl(base->len), length);
+                               (u_int32_t)ntohl(base.len), length);
                }
        }
 }